Application of the Truhlar basis set extrapolation procedure to ab initio calculations on van der Waals complexes

Abstract

The simple basis set extrapolation procedure recently proposed by Truhlar [1998, Chem. Phys. Lett., 294, 45] has been applied to ab initio calculations on van der Waals clusters. Six test species, Ne₂, NeAr, Ar₂, ArH, ArFH and ArHF, were investigated. In general good agreement has been found with complete basis estimates of the van der Waals bond lengths and dissociation energies providing (i) the cc-pVDZ and cc-pVTZ basis sets originally employed by Truhlar are augmented by a single set of standard diffuse functions, and (ii) the counterpoise correction is used. Only ArHF yields disappointing results, presumably due to the substantial contribution of induction forces to the binding in this cluster. However, even in this case the calculated dissociation energy is within 15% of the complete basis set limit.